The industrial dissolved oxygen meter is a device for measuring the dissolved oxygen in water. Its principle of operation is that oxygen is reduced from the working electrode through the diaphragm and a diffusion current proportional to the oxygen concentration is generated. By measuring this current, the concentration of dissolved oxygen in the water is determined.
Depending on the concentration, diaphragm electrodes are divided into two types: polarographic and galvanic.
The polarographic diaphragm electrode uses silver-silver chloride as the counter electrode, the electrolyte inside the electrode is chlorine*potassium, and the outside of the electrode is made of polyethylene and polytetrafluoroethylene with a thickness of 25-50μm film, the film blocks fluid exchange inside and outside the electrode, allowing oxygen dissolved in the water to enter the electrode. The tension between the two Eelectrodes is regulated to 0.5-0.8 V. The dissolved oxygen concentration can be adjusted known by measuring the diffusion current through the external circuit.
Primary batteries use silver as the positive electrode and lead as the negative electrode. The anode and silver electrodes are immersed in the potassium hydroxide electrolytic cell, forming two half-cells whose outer layers are also sealed with a membrane.
The dissolved oxygen is reduced at the anode to create a diffusion current. The dissolved oxygen concentration can be determined by measuring the diffusion current.